Bug 133059

Summary: Simplify RenderLayerCompositor::updateCompositingDescendantGeometry()
Product: WebKit Reporter: Simon Fraser (smfr) <simon.fraser>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal    
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   

Description Simon Fraser (smfr) 2014-05-18 21:33:12 PDT 
RenderLayer::updateLayerPositions(), which is called on every layer after layout, does backing()->updateAfterLayout() which can call compositor().updateCompositingDescendantGeometry().

This is a potentially O(^2) (but I don't think it ever gets this bad because the tee walk is truncated in various ways). I think it might better to just do a RenderLayerCompositor::updateLayerTreeGeometry() after layout if !compositingLayersNeedRebuild().